Concomitant rash and blood dyscrasias in geriatric psychiatry patients treated with carbamazepine.

BACKGROUND

Rashes and blood dyscrasias are disconcerting adverse effects associated with carbamazepine therapy. Rashes are quite common, as are mild blood dyscrasias, such as mild leukopenias. Fortunately, severe rashes and blood dyscrasias are rare. There are few reports on the relationship between carbamazepine-induced rashes and blood dyscrasias, including a prospective study in which rash appeared concomitantly with leukopenia and/or thrombocytopenia in 10 patients, two case reports in which simultaneous rash and agranulocytosis occurred, and two case reports in which rashes served as harbingers of fatal aplastic anemia.

CASE REPORTS

We report two cases of concomitant rashes and blood dyscrasias in geriatric psychiatry patients receiving carbamazepine therapy for bipolar disorder. One patient was found to have a severe leukopenia within several days after rash onset. The other patient was discovered to have a severe leukopenia and thrombocytopenia within about a month after rash onset.

DISCUSSION

Current hematologic monitoring guidelines for carbamazepine rely heavily on the recognition of signs and symptoms of blood dyscrasias by clinicians and patients. We believe that our cases support the suggestion that patients who develop rashes receive more vigilant monitoring of the complete blood count, should carbamazepine therapy by continued. Given the currently available case reports and the fact that the incidence of drug-induced blood dyscrasias increases with advanced age, this recommendation may be particularly relevant for geriatric patients.

CONCLUSIONS

Further study is required to establish whether carbamazepine-induced concomitant rashes and blood dyscrasias are valid associations insofar as monitoring is concerned.